What is more interesting is that only that page is overwritten: The page before and after it stays the same.
~Haohui
On Apr 19, 2012, at 1:40 PM, Haohui Mai wrote:
Hi,
I'm encountering a problem where the memory region of BOOTFS of L4Re got overwritten. Interestingly, the page is overwritten by things in the bootfs.
Here are the physical memory mapping set up by BOOTFS:
... BOOTFS: [2227000-23297b8] [C:506000] rtc BOOTFS: [232a000-26d5411] [C:507000] mag BOOTFS: [26d6000-2848a94] [C:508000] fb-drv BOOTFS: [129d000-129daa4] [C:509000] vandroid-x86.cfg BOOTFS: [126b000-126b3b7] [C:50a000] x86-legacy.devs …
The page 0x2239000 (which belongs to rtc) is magically overwritten by the first page of x86-legacy.devs. I confirmed it with both JDB and QEMU monitor.
I'm running the newest snapshot of L4Re / L4Android on top of the UP version L4.Fiasco kernel.
What would be the best approach to debug the problem? is it there a way to mark the whole BOOTFS as read-only so that I can figure out what's going on?
Thanks!
~Haohui